// webpack打包的配置文件
'use strict'

// 遵循nodejs里面的 commonjs导包的一种规范
//  - 导入    require('包名')  || require('文件的路径')
//  - 导出    module.exports  || exports
const path = require('path')
const defaultSettings = require('./src/settings.js')

// 此resolve函数可以将传入 相对路径变成绝对路径
function resolve(dir) {
  //  __dirname: 获取当前文件所在的目录的绝对路径
  return path.join(__dirname, dir)
}

// 网页标题的名字
const name = defaultSettings.title || 'vue Admin Template' // page title

// If your port is set to 80,

// 项目启动运行的端口号
const port = process.env.port || process.env.npm_config_port || 9528 // dev port

// 脚手架相关的配置 vue-cli   https://cli.vuejs.org/config/
module.exports = {
  /**
   * You will need to set publicPath if you plan to deploy your site under a sub path,
   * for example GitHub Pages. If you plan to deploy your site to https://foo.github.io/bar/,
   * then publicPath should be set to "/bar/".
   * In most cases please use '/' !!!
   * Detail: https://cli.vuejs.org/config/#publicpath
   */
  // publicPath 导出资源（导包成功dist目录）目录是否可以 以相对路径的方式打开
  // - '/' 在服务器的环境下运行 ||  './' 任何环境 相对路径的方式打开文件
  publicPath: '/',
  // 配置打包输出目录的名字
  outputDir: 'dist',
  // 配置打包生成存放静态资源目录的名字，存放js css img
  assetsDir: 'static',
  // 是否开启eslint
  lintOnSave: process.env.NODE_ENV === 'development',
  // 是否开启map映射
  productionSourceMap: false,
  // 脚手架静态服务器相关配置
  devServer: {
    port: port, // 端口号
    open: true, // 是否自动打开浏览器
    // 代理配置
    proxy: {
      // 如果请求地址以/api打头,就出触发代理机制
      // http://localhost:8888/api/sys/login ->  http://ihrm.itheima.net/api/sys/login
      '/api': {
        // target: 'http://192.168.103.30:3000' // 老师端
        target: 'http://ihrm.itheima.net' // 我们要代理的真实接口地址
        // target: 'http://192.168.2.8:3000'  // 傅凯端
      }
    },
    // 错误提示是否在浏览器展示
    overlay: {
      warnings: false,
      errors: true
    }

  },
  // webpack【对象配置】
  configureWebpack: {
    // provide the app's title in webpack's name field, so that
    // it can be accessed in index.html to inject the correct title.
    name: name,
    resolve: {
      alias: {
        '@': resolve('src')
      }
    }
  },
  // webpack 【函数配置】
  chainWebpack(config) {
    // it can improve the speed of the first screen, it is recommended to turn on preload
    config.plugin('preload').tap(() => [
      {
        rel: 'preload',
        // to ignore runtime.js
        // https://github.com/vuejs/vue-cli/blob/dev/packages/@vue/cli-service/lib/config/app.js#L171
        fileBlacklist: [/\.map$/, /hot-update\.js$/, /runtime\..*\.js$/],
        include: 'initial'
      }
    ])

    // when there are many pages, it will cause too many meaningless requests
    config.plugins.delete('prefetch')

    // set svg-sprite-loader
    config.module
      .rule('svg')
      .exclude.add(resolve('src/icons'))
      .end()
    config.module
      .rule('icons')
      .test(/\.svg$/)
      .include.add(resolve('src/icons'))
      .end()
      .use('svg-sprite-loader')
      .loader('svg-sprite-loader')
      .options({
        symbolId: 'icon-[name]'
      })
      .end()

    config
      .when(process.env.NODE_ENV !== 'development',
        config => {
          config
            .plugin('ScriptExtHtmlWebpackPlugin')
            .after('html')
            .use('script-ext-html-webpack-plugin', [{
            // `runtime` must same as runtimeChunk name. default is `runtime`
              inline: /runtime\..*\.js$/
            }])
            .end()
          config
            .optimization.splitChunks({
              chunks: 'all',
              cacheGroups: {
                libs: {
                  name: 'chunk-libs',
                  test: /[\\/]node_modules[\\/]/,
                  priority: 10,
                  chunks: 'initial' // only package third parties that are initially dependent
                },
                elementUI: {
                  name: 'chunk-elementUI', // split elementUI into a single package
                  priority: 20, // the weight needs to be larger than libs and app or it will be packaged into libs or app
                  test: /[\\/]node_modules[\\/]_?element-ui(.*)/ // in order to adapt to cnpm
                },
                commons: {
                  name: 'chunk-commons',
                  test: resolve('src/components'), // can customize your rules
                  minChunks: 3, //  minimum common number
                  priority: 5,
                  reuseExistingChunk: true
                }
              }
            })
          // https:// webpack.js.org/configuration/optimization/#optimizationruntimechunk
          config.optimization.runtimeChunk('single')
        }
      )
  }
}
